The present invention relates in general to apparatus for performing matrix multiplication of a plurality (n) of input signals by a matrix of fixed coefficients (.alpha..sub.nm) to provide a plurality (m) of output signals, all of which are simultaneously available.
This application relates to improvements in the apparatus of copending patent application Ser. No. 852,501, filed Nov. 17, 1977 and assigned to the assignee of the present application.
Many signal processing applications such as deriving the Fourier spectrum of a signal require complex calculations. For example, to obtain the discrete Fourier transform consisting of a plurality of output data points of an analog signal, a series of samples of the input signal are multiplied by a matrix of fixed coefficients having as many fixed coefficients in a row as in a column of the matrix to provide a corresponding series of output signals representing the various frequency components of the analog signal. Heretofore, such calculations were performed by digital computing apparatus involving a multiplicity of calculations as well as a multiplicity of conversions of analog to digital data prior to performance of the multiplying calculations, and subsequently converting the digital data to analog data after the desired calculations has been performed. Such a method of implementing matrix multiplying signal processing operations is slow and requires considerable apparatus.